Dendritic cells: controllers of the immune system and a new promise for immunotherapy.

The immune system is controlled by dendritic cells (DCs). Just as lymphocytes comprise different subsets, DCs comprise several subsets that differentially control lymphocyte function. In humans, the myeloid pathway includes Langerhans cells (LCs) and interstitial DCs (intDCs). While both subsets produce IL-12, only intDCs make IL-10 and induce B cell differentiation. Another pathway includes plasmacytoid DCs, which promptly secrete large amounts of IFN-alpha/beta viral encounter. Thus, insights into in vivo DC functions are important to understand the launching and modulation of immunity.